The mixture of organoclays and polyolefins, commonly called polyolefin nanocomposites, is highly desired because organoclays can add stiffness and toughness to polyolefin-containing compounds. Polyolefins for plastic structures have been useful since the mid-20th Century. Organoclays, smectite inorganic clays intercalated with organic ions, such as quaternary ammonium, have become useful in the last decade.
The heat stability of nanocomposites has shown to be difficult. PCT Patent Publication WO 2004/063268 (Wermter et al.) has disclosed stabilization of thermoplastic nanocomposites which uses (a) a phenolic antioxidant and/or a processing stabilizer and (b) a mono or polyfunctional compound selected from the class consisting of epoxides, oxazolines, oxazolones, oxazines, isocyanates, and/or anhydrides.